1/*
2 * Copyright (c) 2017, Daniel Gultsch All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification,
5 * are permitted provided that the following conditions are met:
6 *
7 * 1. Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * 2. Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation and/or
12 * other materials provided with the distribution.
13 *
14 * 3. Neither the name of the copyright holder nor the names of its contributors
15 * may be used to endorse or promote products derived from this software without
16 * specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
25 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30package eu.siacs.conversations.utils;
31
32import android.graphics.Color;
33import android.graphics.Typeface;
34import android.support.annotation.ColorInt;
35import android.text.Editable;
36import android.text.ParcelableSpan;
37import android.text.Spanned;
38import android.text.TextWatcher;
39import android.text.style.ForegroundColorSpan;
40import android.text.style.StrikethroughSpan;
41import android.text.style.StyleSpan;
42import android.text.style.TypefaceSpan;
43import android.widget.EditText;
44
45import java.util.Arrays;
46import java.util.List;
47
48import eu.siacs.conversations.entities.Message;
49import eu.siacs.conversations.ui.text.QuoteSpan;
50
51public class StylingHelper {
52
53 private static List<? extends Class<? extends ParcelableSpan>> SPAN_CLASSES = Arrays.asList(
54 StyleSpan.class,
55 StrikethroughSpan.class,
56 TypefaceSpan.class,
57 ForegroundColorSpan.class
58 );
59
60 public static void clear(final Editable editable) {
61 final int end = editable.length() - 1;
62 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
63 for (ParcelableSpan span : editable.getSpans(0, end, clazz)) {
64 editable.removeSpan(span);
65 }
66 }
67 }
68
69 public static void format(final Editable editable, int start, int end, @ColorInt int textColor) {
70 for (ImStyleParser.Style style : ImStyleParser.parse(editable,start,end)) {
71 final int keywordLength = style.getKeyword().length();
72 editable.setSpan(createSpanForStyle(style), style.getStart() + keywordLength, style.getEnd() - keywordLength + 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
73 makeKeywordOpaque(editable, style.getStart(), style.getStart() + keywordLength, textColor);
74 makeKeywordOpaque(editable, style.getEnd() - keywordLength + 1, style.getEnd() + 1, textColor);
75 }
76 }
77
78 public static void format(final Editable editable, @ColorInt int textColor) {
79 int end = 0;
80 Message.MergeSeparator[] spans = editable.getSpans(0, editable.length() - 1, Message.MergeSeparator.class);
81 for(Message.MergeSeparator span : spans) {
82 format(editable,end,editable.getSpanStart(span),textColor);
83 end = editable.getSpanEnd(span);
84 }
85 format(editable,end,editable.length() -1,textColor);
86 }
87
88 private static ParcelableSpan createSpanForStyle(ImStyleParser.Style style) {
89 switch (style.getKeyword()) {
90 case "*":
91 return new StyleSpan(Typeface.BOLD);
92 case "_":
93 return new StyleSpan(Typeface.ITALIC);
94 case "~":
95 return new StrikethroughSpan();
96 case "`":
97 case "```":
98 return new TypefaceSpan("monospace");
99 default:
100 throw new AssertionError("Unknown Style");
101 }
102 }
103
104 private static void makeKeywordOpaque(final Editable editable, int start, int end, @ColorInt int fallbackTextColor) {
105 QuoteSpan[] quoteSpans = editable.getSpans(start, end, QuoteSpan.class);
106 @ColorInt int textColor = quoteSpans.length > 0 ? quoteSpans[0].getColor() : fallbackTextColor;
107 @ColorInt int keywordColor = transformColor(textColor);
108 editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
109 }
110
111 private static
112 @ColorInt
113 int transformColor(@ColorInt int c) {
114 return Color.argb(Math.round(Color.alpha(c) * 0.6f), Color.red(c), Color.green(c), Color.blue(c));
115 }
116
117 public static class MessageEditorStyler implements TextWatcher {
118
119 private final EditText mEditText;
120
121 public MessageEditorStyler(EditText editText) {
122 this.mEditText = editText;
123 }
124
125 @Override
126 public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
127
128 }
129
130 @Override
131 public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
132
133 }
134
135 @Override
136 public void afterTextChanged(Editable editable) {
137 clear(editable);
138 format(editable, mEditText.getCurrentTextColor());
139 }
140 }
141}